SHP-1 Regulates Antigen Cross-Presentation and Is Exploited by Leishmania to Evade Immunity.

Intracellular pathogens have evolved strategies to evade detection by cytotoxic CD8 T lymphocytes (CTLs). Here, we ask whether Leishmania parasites trigger the SHP-1-FcRγ chain inhibitory axis to dampen antigen cross-presentation in dendritic cells expressing the C-type lectin receptor Mincle. We find increased cross-priming of CTLs in Leishmania-infected mice deficient for Mincle or with a selective loss of SHP-1 in CD11c cells.

Cell death induced by cytotoxic CD8 T cells is immunogenic and primes caspase-3-dependent spread immunity against endogenous tumor antigens.

Background: Elimination of cancer cells by some stimuli like chemotherapy and radiotherapy activates anticancer immunity after the generation of damage-associated molecular patterns, a process recently named immunogenic cell death (ICD). Despite the recent advances in cancer immunotherapy, very little is known about the immunological consequences of cell death activated by cytotoxic CD8 T (Tc) cells on cancer cells, that is, if Tc cells induce ICD on cancer cells and the molecular mechanisms involved.

Methods: ICD induced by Tc cells on EL4 cells was analyzed in tumor by vaccinating mice with EL4 cells killed or by Ag-specific Tc cells.

Metabolic Control of Dendritic Cell Functions: Digesting Information.

Dendritic cells (DCs) control innate and adaptive immunity by patrolling tissues to gather antigens and danger signals derived from microbes and tissue. Subsequently, DCs integrate those environmental cues, orchestrate immunity or tolerance, and regulate tissue homeostasis. Recent advances in the field of immunometabolism highlight the notion that immune cells markedly alter cellular metabolic pathways during differentiation or upon activation, which has important implications on their functionality.

Effective cancer immunotherapy by natural mouse conventional type-1 dendritic cells bearing dead tumor antigen.

Background: The manipulation of dendritic cells (DCs) for cancer vaccination has not reached its full potential, despite the revolution in cancer immunotherapy. DCs are fundamental for CD8+ T cell activation, which relies on cross-presentation of exogenous antigen on MHC-I and can be fostered by immunogenic cancer cell death. Translational and clinical research has focused on in vitro-generated monocyte-derived DCs, while the vaccination efficacy of natural conventional type 1 DCs (cDC1s), which are associated with improved anti-tumor immunity and specialize on antigen cross-presentation, remains unknown.

Genealogy, Dendritic Cell Priming, and Differentiation of Tissue-Resident Memory CD8 T Cells.

Tissue-resident memory CD8 T (Trm) cells define a distinct non-recirculating subset. Trm cells constitute a first line of defense against local infections in barrier tissues, but they are also found in non-barrier tissues and play a role in antitumor immunity. Their differentiation in tissues and their phenotypical, transcriptional, and functional characteristics are the object of active research.

Lung CD103+ dendritic cells restrain allergic airway inflammation through IL-12 production.

DCs are necessary and sufficient for induction of allergic airway inflammation. CD11b+ DCs direct the underlying Th2 immunity, but debate surrounds the function of CD103+ DCs in lung immunity and asthma after an allergic challenge. We challenged Batf3-/- mice, which lacked lung CD103+ DCs, with the relevant allergen house dust mite (HDM) as a model to ascertain their role in asthma.

Optimal Generation of Tissue-Resident but Not Circulating Memory T Cells during Viral Infection Requires Crosspriming by DNGR-1 Dendritic Cells.

Despite the crucial role of tissue-resident memory T (Trm) cells in protective immunity, their priming remains poorly understood. Here, we have shown differential priming requirements for Trm versus circulating memory CD8 T cells. In vaccinia cutaneous-infected mice, DNGR-1-mediated crosspresentation was required for optimal Trm cell priming but not for their skin differentiation or for circulating memory T cell generation.